SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54f0f9876b1e2a0ab25f69050b1647fcf10facc39f06301d20cec270f9e6e5b2' 
  AND token = '+I1t6yO0xt+CnS4j2jdzWzboNooa7Q3G2CIENiKO5lU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}